To determine the effect of grazing four forage types (chicory, forage rape, high sugar grass, old pasture) on the growth rates of Welsh mountain lambs

To assess the economic advantage for using forage finisher over feed concentrate

Brief description
The trial was located at Bangor University Henfaes Research Centre in the lowland part of the farm. Four forage treatments (chicory/high sugar grass mix, forage rape, white clover/high sugar grass mix, and old pasture (ca. 20 years old)) were used. Twenty lambs of similar live weight were randomly allocated per hectare per each of the four treatments (Figure 1). Lambs were weighed at the start of the experiment and every two weeks thereafter over a period of 6 weeks.
On the final day of the experiment and just before slaughtering date, carcass classification and fat and muscle composition were measured using visual as well as ultrasound scanning machine methods (Figure 2).

The chicory/high sugar grass mix and the white clover/high sugar grass mix treatments gave the most rapid growth rate. The muscle to fat ratio was high (Figure 3). These forages could be suitable for finishing the smaller lambs from upland flock systems quickly.

Forage rape produced the heaviest carcasses, but they had the highest fat content (Figure 3) and took twice as long to finish. Forage rape could be considered as suitable finishing forage for lowland lean breeds which tend not to put on much fat.

Lambs that had been grazing the old pasture performed grew most slowly out of all treatments. Muscle content was also lowest in this treatment (Figure 3).

Establishment costs were higher for chicory/high sugar grass mix than they were for forage rape; however forage rape will only persist for one year whereas chicory will persist for five years (subject to the appropriate grazing regime). Although the old pasture would have no establishment costs, it would give the poorest economic return.